First, when connecting, the function would first try to find a (persistent)
link that's already open with the same host, port, dbname and userid. If
one is found, an identifier for it will be returned instead of opening a
new connection.

Second, the connection to the SQL server will not be closed when the
execution of the script ends. Instead, the link will remain open for
future use (cubrid_close() or
cubrid_disconnect() will not close links established by
cubrid_pconnect_with_url()).

alhosts : Specifies the broker information of the standby server, which is
used for failover when it is impossible to connect to the active server.
You can specify multiple brokers for failover, and the connection to the brokers
is attempted in the order listed in alhosts

rctime : An interval between the attempts to connect to the active broker in
which failure occurred. After a failure occurs, the system connects to the
broker specified by althosts (failover), terminates the transaction, and then
attempts to connect to the active broker of the master database at every rctime.
The default value is 600 seconds.

query_timeout : Timeout value (unit: msec.) for query request. Upon timeout,
a message to cancel requesting a query transferred to server is sent. The return
value can depend on the disconnect_on_query_timeout configuration; even though the
message to cancel a request is sent to server, that request may succeed.

disconnect_on_query_timeout : Configures a value whether to immediately return
an error of function being executed upon timeout. The default value is false.

Замечание:

? and : that are used as identifiers
in PHP connection URL can't be included in the password. The following is
an example of a password that is invalid to use as connection URL because it contains
"?:".

$url = "CUBRID:localhost:33000:tdb:dba:12?:?login_timeout=100";

Passwords that contain ? or : may be
passed as a separate parameter.

$url = "CUBRID:localhost:33000:tbd:::?login_timeout=100";

$conn = cubrid_pconnect_with_url ($url, "dba", "12?");

If user or password is empty,you can't delete ":",the following is
an example.